Router guide for steps and shelves



Sept. 24, 1963 l. l.. PIPER ET AL ROUTER GUIDE FOR STEPS AND SHELVES 3 Sheets-Sheet l Filed April 13, 1961 {VER PIPER Sept. 24, 1963 l. 1 PIPER ETAL ROUTER GUIDE FOR STEPS AND SHELVES 3 Sheets-Sheet 2 Filed April l5, 1961 mvENToRs DAVID E PIPER FRANK NA PIPER IVER L. PIPER Sept. 24, 1963 1. l.. PIPER ET AL 3,104,689

` ROUTER GUIDE FOR STEPS AND SHELVES Filed April 13, 1961 5 Sheets-Sheet 3 FIG.' 5

INVENTORS DAVID E- PIPER FRANK N. PIPER IVER I PIPER United States Patent O 3,104,689 ROUTER GUlDE FR STEPS AND SHELVES Iver L. Piper, David E. Piper, and Frank N. Piper, all of 3709 Jones St., (lmaha, Nebr. Filed Apr. 13, 1961, Ser. No. 102,722 3 Claims. (Cl. l44-l36) This invention relates to tools, particularly used by carpenters in routing stringers for stairs `and side boards for shelves, and the like, and in particular a guide for routing drills or cutters in which the tool guiding elements are set to angular positions on a graduated scale so that dividing the distance between floors to obtain the riser height or the length of the well to obtain the tread is obviated.

The purpose of this invention is to provide a router guide for steps and shelves in which the guide may be moved along an edge of a `Stringer or wall of a cabinet and temporarily secured in positionas a routing tool is actuated.

'In the conventional manner of cutting stringers for steps and cabinet walls for shelves, the height is divided by the number of `steps to obtain the rise of each step and the length of the well is divided by the tread, the number of treads being one less than the number of risers, and in such calculations mistakes are often made resulting in loss of time and damage to material.

Assuming, as an illustration, the height equals 9G inches and the tread l inches; heretofore it has been necessary for a carpenter to figure out a ri-se which is such that it will divide an equal number of times into the height. This has involved a mathematical computation which is not simple and which often results in errors. In this illustration there would be twelve risers, each 71/2 inches and eleven treads. The next step is to lay a carpenters square on a Stringer so that the ten inch mark on one edge of the square is on the upper edge of the stringer and the 71/2 inch mark on the other edge of the square is on the upper edge of the Stringer. The next step is to mark along one edge of the square to indicate the position of a tread or step, also making a mark at the upper edge of the riser, the forward edge, and at a point to indicate where to lay the square on the riser for the next step. This process is repeated with placing the ysquare in successive positions along the striuger. In this process many mistakes are made and even experienced carpenters nd that they make at least one mistake in building each set of steps, particularly where there are interruptions by other workmen. With this thought in mind this invention contemplates a router guide in which substantially all possibility of error is eliminated.

The object of this invention is, therefore, to provide a router guide for steps and shelves in which openings for all steps or shelves of a particular installation are cut by the same setting of the tool.

Another object of the invention is to provide a router guide that travels along an edge of a `Stringer so that slots for all steps of a stairway are equidistant from one edge of the stringer.

Another important object of the invention is to provide a router guide, particularly designed for cutting slot-s in stringers for steps in which the angle of the guide in relation to the head of the tool is set by graduations on parts of the tool. l

It is yet another object of the invention to provide a router guide for steps and shelves in which means is provided for temporarily securing the guide to a Stringer during the cutting operation.

A further object of the invention is to provide a router guide for cutting slots in stringers, side or end Walls, and the like in which parallel arms of the guide are retained 2 in adjusted positions by a clamp including a threaded stud and thumb nut.

A still further object of the invention is to provide a router guide for steps, shelves and the like, in which parallel arms .are held together by adjusting elements, in which the adjusting elements are positioned below the upper surfaces of the arms so that such elements are out of the path of a drill or other cutting tool or of mount' ing elements thereof.

And a still further object is to provide a rounter guide for cutters cutting slots for steps, shelves and fthe like in which the guide is of 1a simple` and economical constmction.

Other and further objects and advantages of the present invention will be apparent from the following detailed description, drawings and claims, the scope of the invention not being limited tothe drawings themselves as the drawings `are only for the purpose of illustrating a method in which the principles of this invention can be applied.

Other embodiments of the invention utilizing the same or equivalent principles may be use-d and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

-ln the drawings: l

FIGURE 1 is a plan view of the router guide for steps `and shelves with part of one side of the guide broken away and with parallel arms of the guide shown in an angular or adjusted po-sition in broken lines.

FIGURE 2 is an end elevational view of the guide showing the guide on a Stringer. v

FIGURE 3 is `a view showing a cross section through the adjustable connectionbetween outer portions of the arms of a router guide taken on line 3`3 of FIGURE l.

FIGURE 4 is a view showing a section through the mounting of one of the pins for temporarily holding the guide in .a routing operation, taken on line 4 4 of FIG- URE 1.

FIGURE 5 is .a view showing :a longitudinal section through a stairway'showing the relative positions of steps land stringers of a stairway.

FIGURE 6 is a view illustrating the position of the router guide in use for cutting slots for steps in a Stringer of a stairway.

While one embodiment of the invention is illustrated in the -aboVe-referred-to drawings, it is tto beunderstood that they yare merely for the purpose of illustration and that various changes in construction may be resorted to in the course of manufacture in `order that the invention may be utilized to the best advantage according to circumstances which may arise, without in any manner departing from the spirit and intention of thek device, which is to be limited only in accordance with the yappended claims. And while there is Istated the primary field of utility of the invention it remains obvious that it may be employed in any other capacity wherein it may be found applicable.

In the accompanying drawings, and in the following specification, the same reference characters are used to designateA 4the same parts and'elements throughout, and in which the numeral lil refers to the invention in its entirety, numeral 12 indicating a semi-circula-r head having a tongue 14 at the center, numeral 16 indicating a guide bar on which the head is pivotally mounted by a pin l18, numerals Ztl and 22 indicating arms adjustably mounted on the head, numeral 24 indicating a holder for clamping the head in adjusted positions on the bar, and numeral 25 a point at the end of an arm 28 extended from the bar and positioned to register with` grad-nations 3d on the head.

The inner ends of the arms 20 and Z2 arev provided with wings 32 and 34 and the wings are provided with slots 36 in which screws 38, threaded in ends of the head 12, are positioned. The inner ends of the arms are also provided with threaded sockets 4Q and 42 in which threaded ends 44 and 46 of an adjusting screw 48 are positioned. The screw d3 is rotatably mounted in bearings 50 and 52 on the tongue 14 and an adjusting nut Se, integral with the screw, is positioned between the bearings. With right hand threads on one end of the screw and lett hand threads on the opposite end the arms 2t) and 22 are moved outwardly or inwardly by turning the nut 54.

The outer end of the arm 2t)l is provided with a pin56 that extends into a socket 58, and the pin is retained in adjusted positions by a threaded stud 69 which extends from the pin 56 through a slot 62 in the socket 58, and which is provided with a thumb nut '64. The pin 56 extends from a slider 66 having a dove-tail tongue 65 ou the outer surface and the tongue is mounted to slide in a groove 7G in the arm 20. The socket 5S extends lfrom a similar slider 72 having a tongue 74 on the outer surface, and the tongue 74 is positioned to slide in a dovetail groove 76 in the arm 22. The slider l66 is provided with a set screw 7S, and a similar set screw Sti is provided in the slider 72. By this means the connection between the arms 20 and 22 may be secured in adiusted positions.

The arms of the router guide are anchored in set positions on a Stringer by pins `82, as shown in FIGURE 4, wherein the pins are positioned in openings 84, with intermediate counter-bores 86 in which springs S8 .are positioned,and large counter-bores 90 in which washers 92 are positioned. The washers 92 are seated on shoulders V94 and the outer portions are provided with countersunk recesses 96 that receive frustro-conical-shaped heads 98 of the pins S2. The pins 82 are provided with collars 100 that engage upper ends ofthe springs, and the lower ends of the springs are seated' on shoulders 104 at the lower ends of the 4counter-bores 86. The springs urge the pins outwardly so that as soon as the guide is drawn away from Ithe stringer, or the like, the pins are snapped upwardly into the openings of the arms. The lower ends of the pins 82 `are provided with points4 106, and when the pins are struck with a hammer, or the like, they are driven downwardly to the positions indicated by the dotted lines 108. f

The router guide is provi-ded with a holder 24 `to clamp the head 12 on the bar 16, and, as shown in FIGURES 1 and 2, the holder is provided with a stud 110 that is secured, such as by welding, to the bar 16, and the upper part of the base is provided with la lip 112 that extends over the head 12. The stud is provided with a thumb nut 114 and a lock washer 116 is provided between the nut and base, to which the numeral 24 refers. By this means the head 12 is clamped upon the bar 16.

The arm 28 which carries the point 26 is positioned against the under side of the bar 16 and the outer end extends upward-ly'providing `a post 118 from the upper end of which the point 26 extends. The pin 1S extends upwardly from the bar 16 and a hub i2@ on the end of the tongue 14 is pivotally mounted thereon. In operation the toll-owing steps are involved:

First, it is presumed that the user is provided with three charts. 'Each chart has a grid with numbers indicating possible threads in inches and possible risers in inches whereby the proper tread dimension for each possible niser dimension is listed. These charts are not shown here as they :are not a part of the instrument itself.

Chart A has a grid. In other words, chart A tells the number and height of the risers in a given distance between the landing .and the floor and also gives the nurnber `and width of treads.

Chart B tel-ls the `degree to set on the router scale 32 for the determined tread and riser combina-tion chosen from chart A. This way chart vi3 has a grid of degrees on one coordinate and the tread and riser combination on the other coordina-te.

Chart C then gives the nu-mber of inches (d in FIG- URE 5) ,from the top of one of the treads to the top of the adjacent tread which latter figure is the difference between riser heights.

The member 16 is preferably at least sixteen inches ifrom the closest inside point of the opening af to the adjacent end of the scale 122.

In other words, chart C' provides the distance H which is the hypotenuse distance measured along the edge of Stringer 157. rl'he distance H is then marked oi on the Stringer and then the tool is applied to the Stringer for routing. Y

It is not necessary to make marks at the end of each H dimension on the way up the stringer lbecause addition H` will be measurable on the tool itself `along scale 122 whereby no marking of the Stringer is needed.

With the router rguide position accordi-ng -to the above system, the .guide is placed against a Stringer as shown in FIGURE 6, and by use of -a router drill or other suitk -able cutting tool all material is removed Afrom the Iarea A between the arms, head, and spacing clamp.

The 'angle of the arms 120 and 22 is set by the gradua tions 30 on the head 12, the distance between the arms is set by the graduations 122 on the edge of the'bar 16,

and the positions of the spacing elements 66 and 72 are determined by the width of the step, as represented by the graduations i24.

In routing tor shelves and other lright angular positioned elements Ithe parts of the router are set, as shown:VK in ffull lines in FIGURE 1. From the -foregoing description, it is thought tube obvious that a router guide for steps and shelves constructed in accordance with my invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated,

and it will also be obvious that my invention is susceptible v Having now described the invention that which is claimed to be new and desired to be procured by Letters Patent, is:

1. A manually supportable, portable router guide comi prising an elongated bar having a straight `edge having graduations thereon, an indicator arm attached to said bar, 4a head having a substantially semi-circular edge, said head being disposed on the upper side of said bar and said edge having semi-circularly yarranged graduations thereon, means pivotally attaching said head to said bar t at the center of the circle of which said semi-circle is a part, said indicator arm having an indicator means thereon cooperative with said graduations and disposed on a line at a right angle to said straight edge of said bar, said semi-circularly arranged -graduations being positioned Afor cooperation with said indicator means, spaced parallel arms extended from the head, means mounting said arms ou said head in a manner for movement of said arms toward andV away 'from each other and for maintaining said arms parallel at all times, and means operably `correlated with said arms yfor maintaining said arms in setlected positions of spacing.

2. A manully supportable, portable router guide comprising an elongated bar having a straight edge having graduations thereon, an indicator arm att-ached to said bar, Ta head having a substantially semidcircular edge, said Y head being disposed 'on the upper side of said bar and said :edge having semi-circularly arranged graduations thereon, means pivotally attaching said head to said bar at the center of the circle of which said semi-circle .is a part, said indicator arm having an indicator means thereon cooperative with said `graduations and -disposed on .a line at a right angle to said straight edge of said bar, sa-id semi-circularly arranged graduations being positioned for coopera-tion -With said indicator means, spaced parallel larms extended :from `the head, an adjusting screw having right hand threads on one end and left hand threads on the opposite end rotatably mounted on the head and positioned with ythe ends threaded in inner ends .of the arms whereby rotation of the screw adjusts the `dis-tance between .the arms.

3. A manually supportable, portable router guide cornprising van elongated bar having a straight edge having graduations thereon, an indicator arm attached to said bar, a head having a substantially semi-circular edge, said head being disposed on the upper side of said bar and said edge having semi-circularly arranged -graduations thereon, means pivotally attaching said head to said bar at the center of the `circle of which said semi-circle is a part, said indicator arm having an indicator means thereo-n cooperative with said :graduations and disposed on a line related With said arms yfor maintaining said arms in se-v looted positions of spacing, adjustable lapping connection members extended from outer ends of those edges of said arms which face each other respectively, means clamping said lapping `connection members into la tixed relationship. Y

References Cited in the iile of this patent UNITED STATES PATENTS 1,161,625 Davison et al. Nov. 23, 1915 1,612,139 Marshall Dec. 218, 1926 1,921,356 Gravell et al Aug. 48, 1933 2,765,820 Perkins Oct. 9, 1956 

1. A MANUALLY SUPPORTABLE, PORTABLE ROUTER GUIDE COMPRISING AN ELONGATED BAR HAVING A STRAIGHT EDGE HAVING GRADUATIONS THEREON, AN INDICATOR ARM ATTACHED TO SAID BAR, A HEAD HAVING A SUBSTANTIALLY SEMI-CIRCULAR EDGE, SAID HEAD BEING DISPOSED ON THE UPPER SIDE OF SAID BAR AND SAID EDGE HAVING SEMI-CIRCULARLY ARRANGED GRADUATIONS THEREON, MEANS PIVOTALLY ATTACHING SAID HEAD TO SAID BAR AT THE CENTER OF THE CIRCLE OF WHICH SAID SEMI-CIRCLE IS A PART, SAID INDICATOR ARM HAVING AN INDICATOR MEANS THEREON COOPERATIVE WITH SAID GRADUATIONS AND DISPOSED ON A LINE AT A RIGHT ANGLE TO SAID STRAIGHT EDGE OF SAID BAR, SAID SEMI-CIRCULARLY ARRANGED GRADUATIONS BEING POSITIONED FOR COOPERATION WITH SAID INDICATOR MEANS, SPACED PARALLEL ARMS EXTENDED FROM THE HEAD, MEANS MOUNTING SAID ARMS ON SAID HEAD IN A MANNER FOR MOVEMENT OF SAID ARMS TOWARD AND AWAY FROM EACH OTHER AND FOR MAINTAINING SAID ARMS PARALLEL AT ALL TIMES, AND MEANS OPERABLY CORRELATED WITH SAID ARMS FOR MAINTAINING SAID ARMS IN SELECTED POSITIONS OF SPACING. 